Technetium

Technetium (Tc)

Radioactive metallic transition element. Can be detected in some stars and the fission products of uranium. First made by Perrier and Segre by bombarding molybdenum with deutrons, giving them Tc-97. Tc-99 is the most stable isotope with a half-life of 2.6*10^6 years. Sixteen isotopes are known. Organic technetium compounds are used in bone imaging. Chemical properties are intermediate between rhenium and manganese.
Atomic Number43
Atomic Weight97.90721
Mass Number83
Group7
Period5
Blockd
Protons43 p+
Neutrons40 n0
Electrons43 e-
Technetium-sample.jpg Electron shell 043 technetium.png Animated Bohr Model of Tc (Technetium) Enhanced Bohr Model of Tc (Technetium) Bohr Model: Tc (Technetium) Orbital Diagram of Tc (Technetium)

Properties

Atomic Radius
135 pm
Molar Volume
Covalent Radius
128 pm
Metallic Radius
127 pm
Ionic Radius
64.5 pm
Crystal Radius
78.5 pm
Van der Waals Radius
216 pm
Density
Energy
Proton Affinity
Electron Affinity
Ionization Energy
7.119381 eV/particle
Heat of Vaporization
585 kJ/mol
Heat of Fusion
23.8 kJ/mol
Heat of Formation
678 kJ/mol
Electrons
Electron Shells2, 8, 18, 13, 2
Valence Electrons6
Electron Configuration[Kr] 4d5 5s2
Oxidation States-3, -1, 0, 1, 2, 3, 4, 5, 6, 7
Electronegativity
2.1
Electrophilicity
1.1191961031633155 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
4,535.15 K
Melting Point
2,430.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Silver
Appearanceshiny gray metal
Refractive Index
Thermodynamic Properties
Thermal Conductivity
50.6 W/(m K)
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
5 MS/m
Electrical Resistivity
0.0000002 m Ω
Superconducting Point
7.7 K
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.0000000342 m³/Kg
Magnetic Susceptibility (Molar)
0.000000003352 m³/mol
Magnetic Susceptibility (Volume)
0.0003933
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal StructureSimple Hexagonal (HEX)
Lattice Constant
2.74 Å
Lattice Anglesπ/2, π/2, 2 π/3
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
Classification
CategoryTransition metals, Transition metals
CAS GroupVIIA
IUPAC GroupVIIB
Glawe Number59
Mendeleev Number56
Pettifor Number58
Geochemical Class
Goldschmidt Classsynthetic
Other
Gas Basicity
Dipole Polarizability
79 ± 10 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
22
Neutron Mass Absorption
Quantum Numbers6S5/2
Space Group194 (P63/mmc)

Isotopes of Technetium

Stable Isotopes0
Unstable Isotopes40
Radioactive Isotopes37

83Tc

Abundance
Relative Atomic Mass
82.966377 ± 0.000537 Da
Mass Number83
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity-

83Tc Decay Modes
Decay ModeIntensity
p (proton emission)%
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

84Tc

Abundance
Relative Atomic Mass
83.959527 ± 0.000429 Da
Mass Number84
G-Factor
Half Life
Spin1
Quadrupole Moment
Discovery Year
Parity+

84Tc Decay Modes
Decay ModeIntensity
p (proton emission)%
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

85Tc

Abundance
Relative Atomic Mass
84.950778 ± 0.000429 Da
Mass Number85
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity-

85Tc Decay Modes
Decay ModeIntensity
p (proton emission)%

86Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
85.944637 ± 0.000322 Da
Mass Number86
G-Factor
0
Half Life
55 ± 7 ms
Spin0
Quadrupole Moment
0
Discovery Year1992
Parity+

86Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

87Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
86.938067185 ± 0.0000045 Da
Mass Number87
G-Factor
Half Life
2.14 ± 0.17 s
Spin9/2
Quadrupole Moment
Discovery Year1991
Parity+

87Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)0.7%

88Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
87.933794211 ± 0.0000044 Da
Mass Number88
G-Factor
Half Life
6.4 ± 0.8 s
Spin2
Quadrupole Moment
Discovery Year1991
Parity+

88Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

89Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
88.927648649 ± 0.0000041 Da
Mass Number89
G-Factor
Half Life
12.8 ± 0.9 s
Spin9/2
Quadrupole Moment
Discovery Year1991
Parity+

89Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

90Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
89.924073919 ± 0.0000011 Da
Mass Number90
G-Factor
Half Life
49.2 ± 0.4 s
Spin8
Quadrupole Moment
Discovery Year1974
Parity+

90Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

91Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
90.918424972 ± 0.000002536 Da
Mass Number91
G-Factor
Half Life
3.14 ± 0.02 m
Spin9/2
Quadrupole Moment
Discovery Year1974
Parity

91Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

92Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
91.915269777 ± 0.00000333 Da
Mass Number92
G-Factor
Half Life
4.25 ± 0.15 m
Spin8
Quadrupole Moment
Discovery Year1964
Parity

92Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

93Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
92.910245147 ± 0.000001086 Da
Mass Number93
G-Factor
1.4044444444444 ± 0.013333333333333
Half Life
2.75 ± 0.05 h
Spin9/2
Quadrupole Moment
Discovery Year1948
Parity+

93Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

94Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
93.909652319 ± 0.00000437 Da
Mass Number94
G-Factor
0.73142857142857 ± 0.0071428571428571
Half Life
293 ± 1 m
Spin7
Quadrupole Moment
Discovery Year1948
Parity+

94Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

95Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
94.907652281 ± 0.000005453 Da
Mass Number95
G-Factor
1.32 ± 0.013333333333333
Half Life
19.258 ± 0.026 h
Spin9/2
Quadrupole Moment
Discovery Year1947
Parity+

95Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

96Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
95.907866675 ± 0.000005524 Da
Mass Number96
G-Factor
0.72714285714286 ± 0.0071428571428571
Half Life
4.28 ± 0.07 d
Spin7
Quadrupole Moment
Discovery Year1947
Parity+

96Tc Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

97Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
96.90636072 ± 0.00000442 Da
Mass Number97
G-Factor
1.2933333333333 ± 0.02
Half Life
4.21 ± 0.16 My
Spin9/2
Quadrupole Moment
Discovery Year1946
Parity+

97Tc Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

98Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
97.907211206 ± 0.000003628 Da
Mass Number98
G-Factor
Half Life
4.2 ± 0.3 My
Spin6
Quadrupole Moment
Discovery Year1955
Parity+

98Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β+ (β+ decay; β+ = ϵ + e+)0%

99Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
98.906249681 ± 0.000000974 Da
Mass Number99
G-Factor
Half Life
211.1 ± 1.2 ky
Spin9/2
Quadrupole Moment
-0.129 ± 0.006
Discovery Year1938
Parity+

99Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

100Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
99.907652715 ± 0.00000145 Da
Mass Number100
G-Factor
Half Life
15.46 ± 0.19 s
Spin1
Quadrupole Moment
Discovery Year1952
Parity+

100Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
ϵ (electron capture)0.0018%

101Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
100.907305271 ± 0.000025768 Da
Mass Number101
G-Factor
Half Life
14.22 ± 0.01 m
Spin9/2
Quadrupole Moment
Discovery Year1941
Parity+

101Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

102Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
101.909207239 ± 0.00000984 Da
Mass Number102
G-Factor
Half Life
5.28 ± 0.15 s
Spin1
Quadrupole Moment
Discovery Year1954
Parity+

102Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

103Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
102.90917396 ± 0.000010531 Da
Mass Number103
G-Factor
Half Life
54.2 ± 0.8 s
Spin5/2
Quadrupole Moment
Discovery Year1957
Parity+

103Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

104Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
103.911433718 ± 0.000026716 Da
Mass Number104
G-Factor
Half Life
18.3 ± 0.3 m
Spin3
Quadrupole Moment
Discovery Year1956
Parity-

104Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

105Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
104.911662024 ± 0.000037856 Da
Mass Number105
G-Factor
Half Life
7.64 ± 0.06 m
Spin3/2
Quadrupole Moment
Discovery Year1955
Parity-

105Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

106Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
105.914356674 ± 0.00001315 Da
Mass Number106
G-Factor
Half Life
35.6 ± 0.6 s
Spin1
Quadrupole Moment
Discovery Year1965
Parity

106Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

107Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
106.915458437 ± 0.00000931 Da
Mass Number107
G-Factor
Half Life
21.2 ± 0.2 s
Spin3/2
Quadrupole Moment
Discovery Year1965
Parity-

107Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

108Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
107.918493493 ± 0.000009413 Da
Mass Number108
G-Factor
Half Life
5.17 ± 0.07 s
Spin2
Quadrupole Moment
Discovery Year1970
Parity

108Tc Decay Modes
Decay ModeIntensity
β (β decay)100%

109Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
108.920254107 ± 0.00001038 Da
Mass Number109
G-Factor
Half Life
905 ± 21 ms
Spin5/2
Quadrupole Moment
Discovery Year1976
Parity+

109Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.08%

110Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
109.923741263 ± 0.000010195 Da
Mass Number110
G-Factor
Half Life
900 ± 13 ms
Spin2
Quadrupole Moment
Discovery Year1976
Parity+

110Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.04%

111Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
110.925898966 ± 0.000011359 Da
Mass Number111
G-Factor
Half Life
350 ± 11 ms
Spin5/2
Quadrupole Moment
Discovery Year1988
Parity+

111Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.85%

112Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
111.929941658 ± 0.00000592 Da
Mass Number112
G-Factor
Half Life
323 ± 6 ms
Spin2
Quadrupole Moment
Discovery Year1990
Parity+

112Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)1.5%

113Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
112.932569032 ± 0.0000036 Da
Mass Number113
G-Factor
Half Life
152 ± 8 ms
Spin5/2
Quadrupole Moment
Discovery Year1992
Parity+

113Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)2.1%

114Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
113.93709 ± 0.000465 Da
Mass Number114
G-Factor
Half Life
121 ± 9 ms
Spin5
Quadrupole Moment
Discovery Year1994
Parity+

114Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)1.3%

115Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
114.9401 ± 0.00021 Da
Mass Number115
G-Factor
Half Life
78 ± 2 ms
Spin5/2
Quadrupole Moment
Discovery Year1994
Parity+

115Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

116Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
115.94502 ± 0.00032 Da
Mass Number116
G-Factor
Half Life
57 ± 3 ms
Spin2
Quadrupole Moment
Discovery Year1997
Parity+

116Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

117Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
116.94832 ± 0.000429 Da
Mass Number117
G-Factor
Half Life
44.5 ± 3 ms
Spin5/2
Quadrupole Moment
Discovery Year1997
Parity+

117Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

118Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
117.953526 ± 0.000429 Da
Mass Number118
G-Factor
Half Life
30 ± 4 ms
Spin2
Quadrupole Moment
Discovery Year2010
Parity+

118Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

119Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
118.956876 ± 0.000537 Da
Mass Number119
G-Factor
Half Life
22 ± 3 ms
Spin5/2
Quadrupole Moment
Discovery Year2010
Parity+

119Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

120Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
119.962426 ± 0.000537 Da
Mass Number120
G-Factor
Half Life
21 ± 5 ms
Spin3
Quadrupole Moment
Discovery Year2010
Parity+

120Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

121Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
120.96614 ± 0.000537 Da
Mass Number121
G-Factor
Half Life
22 ± 6 ms
Spin5/2
Quadrupole Moment
Discovery Year2015
Parity+

121Tc Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

122Tc

AbundanceRadioactive ☢️
Relative Atomic Mass
121.97176 ± 0.000322 Da
Mass Number122
G-Factor
Half Life
Spin1
Quadrupole Moment
Discovery Year2018
Parity+

122Tc Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%
2n (2-neutron emission)%

History

Element 43 was predicted on the basis of the periodic table, and was erroneously reported as having been discovered in 1925, at which time it was named masurium. The element was actually discovered by Carlo Perrier and Emilio Segrè in 1937. It was also found in a sample of molybdenum sent by Ernest Lawrence that was bombarded by deuterons in the Berkeley cyclotron. From the Greek word technetos, artificial

DiscoverersCarlo Perrier, Émillo Segrè
Discovery LocationItaly
Discovery Year1937
Etymology (Name Origin)Greek: technêtos (artificial).
Pronunciationtek-NEE-shi-em (English)
Technetium is harmful due to its radioactivity
Technetium was the first element to be produced artificially

Uses

Technetium is used in nuclear medicine to carry out a number of medical tests, mainly relating to imaging and functional studies of internal bodily organs like bone scan. It is also used industrially for equipment calibration following its approval as a standard beta emitter. Mild carbon steels may be effectively protected by minute quantities of technetium, but this corrosion protection is limited to closed systems because of technetium's radioactivity. Added to iron in quantities as low as 55 part-per-million transforms the iron into a corrosion-resistant alloy.

Sources

Made first by bombarding molybdenum with deuterons (heavy hydrogen) in a cyclotron.

Abundance
Abundance in Earth's crust
Abundance in Oceans
Abundance in Human Body
0 %
Abundance in Meteor
0 %
Abundance in Sun
0 %
Abundance in Universe
0 %

Nuclear Screening Constants

1s0.891
2p4.0592
2s11.3718
3d14.647
3p16.6159
3s16.2088
4d30.118
4p27.1888
4s25.8016
5s35.7735